fs/hppfs/hppfs_kern.c

   1 /*
   2  * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
   3  * Licensed under the GPL
   4  */
   5
   6 #include <linux/fs.h>
   7 #include <linux/file.h>
   8 #include <linux/module.h>
   9 #include <linux/init.h>
  10 #include <linux/slab.h>
  11 #include <linux/list.h>
  12 #include <linux/kernel.h>
  13 #include <linux/ctype.h>
  14 #include <linux/dcache.h>
  15 #include <linux/statfs.h>
  16 #include <asm/uaccess.h>
  17 #include <asm/fcntl.h>
  18 #include "os.h"
  19
  20 static int init_inode(struct inode *inode, struct dentry *dentry);
  21
  22 struct hppfs_data {
  23         struct list_head list;
  24         char contents[PAGE_SIZE - sizeof(struct list_head)];
  25 };
  26
  27 struct hppfs_private {
  28         struct file *proc_file;
  29         int host_fd;
  30         loff_t len;
  31         struct hppfs_data *contents;
  32 };
  33
  34 struct hppfs_inode_info {
  35         struct dentry *proc_dentry;
  36         struct inode vfs_inode;
  37 };
  38
  39 static inline struct hppfs_inode_info *HPPFS_I(struct inode *inode)
  40 {
  41         return container_of(inode, struct hppfs_inode_info, vfs_inode);
  42 }
  43
  44 #define HPPFS_SUPER_MAGIC 0xb00000ee
  45
  46 static struct super_operations hppfs_sbops;
  47
  48 static int is_pid(struct dentry *dentry)
  49 {
  50         struct super_block *sb;
  51         int i;
  52
  53         sb = dentry->d_sb;
  54         if((sb->s_op != &hppfs_sbops) || (dentry->d_parent != sb->s_root))
  55                 return(0);
  56
  57         for(i = 0; i < dentry->d_name.len; i++){
  58                 if(!isdigit(dentry->d_name.name[i]))
  59                         return(0);
  60         }
  61         return(1);
  62 }
  63
  64 static char *dentry_name(struct dentry *dentry, int extra)
  65 {
  66         struct dentry *parent;
  67         char *root, *name;
  68         const char *seg_name;
  69         int len, seg_len;
  70
  71         len = 0;
  72         parent = dentry;
  73         while(parent->d_parent != parent){
  74                 if(is_pid(parent))
  75                         len += strlen("pid") + 1;
  76                 else len += parent->d_name.len + 1;
  77                 parent = parent->d_parent;
  78         }
  79
  80         root = "proc";
  81         len += strlen(root);
  82         name = kmalloc(len + extra + 1, GFP_KERNEL);
  83         if(name == NULL) return(NULL);
  84
  85         name[len] = '\0';
  86         parent = dentry;
  87         while(parent->d_parent != parent){
  88                 if(is_pid(parent)){
  89                         seg_name = "pid";
  90                         seg_len = strlen("pid");
  91                 }
  92                 else {
  93                         seg_name = parent->d_name.name;
  94                         seg_len = parent->d_name.len;
  95                 }
  96
  97                 len -= seg_len + 1;
  98                 name[len] = '/';
  99                 strncpy(&name[len + 1], seg_name, seg_len);
 100                 parent = parent->d_parent;
 101         }
 102         strncpy(name, root, strlen(root));
 103         return(name);
 104 }
 105
 106 struct dentry_operations hppfs_dentry_ops = {
 107 };
 108
 109 static int file_removed(struct dentry *dentry, const char *file)
 110 {
 111         char *host_file;
 112         int extra, fd;
 113
 114         extra = 0;
 115         if(file != NULL) extra += strlen(file) + 1;
 116
 117         host_file = dentry_name(dentry, extra + strlen("/remove"));
 118         if(host_file == NULL){
 119                 printk("file_removed : allocation failed\n");
 120                 return(-ENOMEM);
 121         }
 122
 123         if(file != NULL){
 124                 strcat(host_file, "/");
 125                 strcat(host_file, file);
 126         }
 127         strcat(host_file, "/remove");
 128
 129         fd = os_open_file(host_file, of_read(OPENFLAGS()), 0);
 130         kfree(host_file);
 131         if(fd > 0){
 132                 os_close_file(fd);
 133                 return(1);
 134         }
 135         return(0);
 136 }
 137
 138 static void hppfs_read_inode(struct inode *ino)
 139 {
 140         struct inode *proc_ino;
 141
 142         if(HPPFS_I(ino)->proc_dentry == NULL)
 143                 return;
 144
 145         proc_ino = HPPFS_I(ino)->proc_dentry->d_inode;
 146         ino->i_uid = proc_ino->i_uid;
 147         ino->i_gid = proc_ino->i_gid;
 148         ino->i_atime = proc_ino->i_atime;
 149         ino->i_mtime = proc_ino->i_mtime;
 150         ino->i_ctime = proc_ino->i_ctime;
 151         ino->i_ino = proc_ino->i_ino;
 152         ino->i_mode = proc_ino->i_mode;
 153         ino->i_nlink = proc_ino->i_nlink;
 154         ino->i_size = proc_ino->i_size;
 155         ino->i_blksize = proc_ino->i_blksize;
 156         ino->i_blocks = proc_ino->i_blocks;
 157 }
 158
 159 static struct dentry *hppfs_lookup(struct inode *ino, struct dentry *dentry,
 160                                   struct nameidata *nd)
 161 {
 162         struct dentry *proc_dentry, *new, *parent;
 163         struct inode *inode;
 164         int err, deleted;
 165
 166         deleted = file_removed(dentry, NULL);
 167         if(deleted < 0)
 168                 return(ERR_PTR(deleted));
 169         else if(deleted)
 170                 return(ERR_PTR(-ENOENT));
 171
 172         err = -ENOMEM;
 173         parent = HPPFS_I(ino)->proc_dentry;
 174         mutex_lock(&parent->d_inode->i_mutex);
 175         proc_dentry = d_lookup(parent, &dentry->d_name);
 176         if(proc_dentry == NULL){
 177                 proc_dentry = d_alloc(parent, &dentry->d_name);
 178                 if(proc_dentry == NULL){
 179                         mutex_unlock(&parent->d_inode->i_mutex);
 180                         goto out;
 181                 }
 182                 new = (*parent->d_inode->i_op->lookup)(parent->d_inode,
 183                                                        proc_dentry, NULL);
 184                 if(new){
 185                         dput(proc_dentry);
 186                         proc_dentry = new;
 187                 }
 188         }
 189         mutex_unlock(&parent->d_inode->i_mutex);
 190
 191         if(IS_ERR(proc_dentry))
 192                 return(proc_dentry);
 193
 194         inode = iget(ino->i_sb, 0);
 195         if(inode == NULL)
 196                 goto out_dput;
 197
 198         err = init_inode(inode, proc_dentry);
 199         if(err)
 200                 goto out_put;
 201
 202         hppfs_read_inode(inode);
 203
 204         d_add(dentry, inode);
 205         dentry->d_op = &hppfs_dentry_ops;
 206         return(NULL);
 207
 208  out_put:
 209         iput(inode);
 210  out_dput:
 211         dput(proc_dentry);
 212  out:
 213         return(ERR_PTR(err));
 214 }
 215
 216 static struct inode_operations hppfs_file_iops = {
 217 };
 218
 219 static ssize_t read_proc(struct file *file, char *buf, ssize_t count,
 220                          loff_t *ppos, int is_user)
 221 {
 222         ssize_t (*read)(struct file *, char *, size_t, loff_t *);
 223         ssize_t n;
 224
 225         read = file->f_dentry->d_inode->i_fop->read;
 226
 227         if(!is_user)
 228                 set_fs(KERNEL_DS);
 229
 230         n = (*read)(file, buf, count, &file->f_pos);
 231
 232         if(!is_user)
 233                 set_fs(USER_DS);
 234
 235         if(ppos) *ppos = file->f_pos;
 236         return n;
 237 }
 238
 239 static ssize_t hppfs_read_file(int fd, char *buf, ssize_t count)
 240 {
 241         ssize_t n;
 242         int cur, err;
 243         char *new_buf;
 244
 245         n = -ENOMEM;
 246         new_buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
 247         if(new_buf == NULL){
 248                 printk("hppfs_read_file : kmalloc failed\n");
 249                 goto out;
 250         }
 251         n = 0;
 252         while(count > 0){
 253                 cur = min_t(ssize_t, count, PAGE_SIZE);
 254                 err = os_read_file(fd, new_buf, cur);
 255                 if(err < 0){
 256                         printk("hppfs_read : read failed, errno = %d\n",
 257                                err);
 258                         n = err;
 259                         goto out_free;
 260                 }
 261                 else if(err == 0)
 262                         break;
 263
 264                 if(copy_to_user(buf, new_buf, err)){
 265                         n = -EFAULT;
 266                         goto out_free;
 267                 }
 268                 n += err;
 269                 count -= err;
 270         }
 271  out_free:
 272         kfree(new_buf);
 273  out:
 274         return n;
 275 }
 276
 277 static ssize_t hppfs_read(struct file *file, char *buf, size_t count,
 278                           loff_t *ppos)
 279 {
 280         struct hppfs_private *hppfs = file->private_data;
 281         struct hppfs_data *data;
 282         loff_t off;
 283         int err;
 284
 285         if(hppfs->contents != NULL){
 286                 if(*ppos >= hppfs->len) return(0);
 287
 288                 data = hppfs->contents;
 289                 off = *ppos;
 290                 while(off >= sizeof(data->contents)){
 291                         data = list_entry(data->list.next, struct hppfs_data,
 292                                           list);
 293                         off -= sizeof(data->contents);
 294                 }
 295
 296                 if(off + count > hppfs->len)
 297                         count = hppfs->len - off;
 298                 copy_to_user(buf, &data->contents[off], count);
 299                 *ppos += count;
 300         }
 301         else if(hppfs->host_fd != -1){
 302                 err = os_seek_file(hppfs->host_fd, *ppos);
 303                 if(err){
 304                         printk("hppfs_read : seek failed, errno = %d\n", err);
 305                         return(err);
 306                 }
 307                 count = hppfs_read_file(hppfs->host_fd, buf, count);
 308                 if(count > 0)
 309                         *ppos += count;
 310         }
 311         else count = read_proc(hppfs->proc_file, buf, count, ppos, 1);
 312
 313         return(count);
 314 }
 315
 316 static ssize_t hppfs_write(struct file *file, const char *buf, size_t len,
 317                            loff_t *ppos)
 318 {
 319         struct hppfs_private *data = file->private_data;
 320         struct file *proc_file = data->proc_file;
 321         ssize_t (*write)(struct file *, const char *, size_t, loff_t *);
 322         int err;
 323
 324         write = proc_file->f_dentry->d_inode->i_fop->write;
 325
 326         proc_file->f_pos = file->f_pos;
 327         err = (*write)(proc_file, buf, len, &proc_file->f_pos);
 328         file->f_pos = proc_file->f_pos;
 329
 330         return(err);
 331 }
 332
 333 static int open_host_sock(char *host_file, int *filter_out)
 334 {
 335         char *end;
 336         int fd;
 337
 338         end = &host_file[strlen(host_file)];
 339         strcpy(end, "/rw");
 340         *filter_out = 1;
 341         fd = os_connect_socket(host_file);
 342         if(fd > 0)
 343                 return(fd);
 344
 345         strcpy(end, "/r");
 346         *filter_out = 0;
 347         fd = os_connect_socket(host_file);
 348         return(fd);
 349 }
 350
 351 static void free_contents(struct hppfs_data *head)
 352 {
 353         struct hppfs_data *data;
 354         struct list_head *ele, *next;
 355
 356         if(head == NULL) return;
 357
 358         list_for_each_safe(ele, next, &head->list){
 359                 data = list_entry(ele, struct hppfs_data, list);
 360                 kfree(data);
 361         }
 362         kfree(head);
 363 }
 364
 365 static struct hppfs_data *hppfs_get_data(int fd, int filter,
 366                                          struct file *proc_file,
 367                                          struct file *hppfs_file,
 368                                          loff_t *size_out)
 369 {
 370         struct hppfs_data *data, *new, *head;
 371         int n, err;
 372
 373         err = -ENOMEM;
 374         data = kmalloc(sizeof(*data), GFP_KERNEL);
 375         if(data == NULL){
 376                 printk("hppfs_get_data : head allocation failed\n");
 377                 goto failed;
 378         }
 379
 380         INIT_LIST_HEAD(&data->list);
 381
 382         head = data;
 383         *size_out = 0;
 384
 385         if(filter){
 386                 while((n = read_proc(proc_file, data->contents,
 387                                      sizeof(data->contents), NULL, 0)) > 0)
 388                         os_write_file(fd, data->contents, n);
 389                 err = os_shutdown_socket(fd, 0, 1);
 390                 if(err){
 391                         printk("hppfs_get_data : failed to shut down "
 392                                "socket\n");
 393                         goto failed_free;
 394                 }
 395         }
 396         while(1){
 397                 n = os_read_file(fd, data->contents, sizeof(data->contents));
 398                 if(n < 0){
 399                         err = n;
 400                         printk("hppfs_get_data : read failed, errno = %d\n",
 401                                err);
 402                         goto failed_free;
 403                 }
 404                 else if(n == 0)
 405                         break;
 406
 407                 *size_out += n;
 408
 409                 if(n < sizeof(data->contents))
 410                         break;
 411
 412                 new = kmalloc(sizeof(*data), GFP_KERNEL);
 413                 if(new == 0){
 414                         printk("hppfs_get_data : data allocation failed\n");
 415                         err = -ENOMEM;
 416                         goto failed_free;
 417                 }
 418
 419                 INIT_LIST_HEAD(&new->list);
 420                 list_add(&new->list, &data->list);
 421                 data = new;
 422         }
 423         return(head);
 424
 425  failed_free:
 426         free_contents(head);
 427  failed:
 428         return(ERR_PTR(err));
 429 }
 430
 431 static struct hppfs_private *hppfs_data(void)
 432 {
 433         struct hppfs_private *data;
 434
 435         data = kmalloc(sizeof(*data), GFP_KERNEL);
 436         if(data == NULL)
 437                 return(data);
 438
 439         *data = ((struct hppfs_private ) { .host_fd             = -1,
 440                                            .len                 = -1,
 441                                            .contents            = NULL } );
 442         return(data);
 443 }
 444
 445 static int file_mode(int fmode)
 446 {
 447         if(fmode == (FMODE_READ | FMODE_WRITE))
 448                 return(O_RDWR);
 449         if(fmode == FMODE_READ)
 450                 return(O_RDONLY);
 451         if(fmode == FMODE_WRITE)
 452                 return(O_WRONLY);
 453         return(0);
 454 }
 455
 456 static int hppfs_open(struct inode *inode, struct file *file)
 457 {
 458         struct hppfs_private *data;
 459         struct dentry *proc_dentry;
 460         char *host_file;
 461         int err, fd, type, filter;
 462
 463         err = -ENOMEM;
 464         data = hppfs_data();
 465         if(data == NULL)
 466                 goto out;
 467
 468         host_file = dentry_name(file->f_dentry, strlen("/rw"));
 469         if(host_file == NULL)
 470                 goto out_free2;
 471
 472         proc_dentry = HPPFS_I(inode)->proc_dentry;
 473
 474         /* XXX This isn't closed anywhere */
 475         data->proc_file = dentry_open(dget(proc_dentry), NULL,
 476                                       file_mode(file->f_mode));
 477         err = PTR_ERR(data->proc_file);
 478         if(IS_ERR(data->proc_file))
 479                 goto out_free1;
 480
 481         type = os_file_type(host_file);
 482         if(type == OS_TYPE_FILE){
 483                 fd = os_open_file(host_file, of_read(OPENFLAGS()), 0);
 484                 if(fd >= 0)
 485                         data->host_fd = fd;
 486                 else printk("hppfs_open : failed to open '%s', errno = %d\n",
 487                             host_file, -fd);
 488
 489                 data->contents = NULL;
 490         }
 491         else if(type == OS_TYPE_DIR){
 492                 fd = open_host_sock(host_file, &filter);
 493                 if(fd > 0){
 494                         data->contents = hppfs_get_data(fd, filter,
 495                                                         data->proc_file,
 496                                                         file, &data->len);
 497                         if(!IS_ERR(data->contents))
 498                                 data->host_fd = fd;
 499                 }
 500                 else printk("hppfs_open : failed to open a socket in "
 501                             "'%s', errno = %d\n", host_file, -fd);
 502         }
 503         kfree(host_file);
 504
 505         file->private_data = data;
 506         return(0);
 507
 508  out_free1:
 509         kfree(host_file);
 510  out_free2:
 511         free_contents(data->contents);
 512         kfree(data);
 513  out:
 514         return(err);
 515 }
 516
 517 static int hppfs_dir_open(struct inode *inode, struct file *file)
 518 {
 519         struct hppfs_private *data;
 520         struct dentry *proc_dentry;
 521         int err;
 522
 523         err = -ENOMEM;
 524         data = hppfs_data();
 525         if(data == NULL)
 526                 goto out;
 527
 528         proc_dentry = HPPFS_I(inode)->proc_dentry;
 529         data->proc_file = dentry_open(dget(proc_dentry), NULL,
 530                                       file_mode(file->f_mode));
 531         err = PTR_ERR(data->proc_file);
 532         if(IS_ERR(data->proc_file))
 533                 goto out_free;
 534
 535         file->private_data = data;
 536         return(0);
 537
 538  out_free:
 539         kfree(data);
 540  out:
 541         return(err);
 542 }
 543
 544 static loff_t hppfs_llseek(struct file *file, loff_t off, int where)
 545 {
 546         struct hppfs_private *data = file->private_data;
 547         struct file *proc_file = data->proc_file;
 548         loff_t (*llseek)(struct file *, loff_t, int);
 549         loff_t ret;
 550
 551         llseek = proc_file->f_dentry->d_inode->i_fop->llseek;
 552         if(llseek != NULL){
 553                 ret = (*llseek)(proc_file, off, where);
 554                 if(ret < 0)
 555                         return(ret);
 556         }
 557
 558         return(default_llseek(file, off, where));
 559 }
 560
 561 static const struct file_operations hppfs_file_fops = {
 562         .owner          = NULL,
 563         .llseek         = hppfs_llseek,
 564         .read           = hppfs_read,
 565         .write          = hppfs_write,
 566         .open           = hppfs_open,
 567 };
 568
 569 struct hppfs_dirent {
 570         void *vfs_dirent;
 571         filldir_t filldir;
 572         struct dentry *dentry;
 573 };
 574
 575 static int hppfs_filldir(void *d, const char *name, int size,
 576                          loff_t offset, ino_t inode, unsigned int type)
 577 {
 578         struct hppfs_dirent *dirent = d;
 579
 580         if(file_removed(dirent->dentry, name))
 581                 return(0);
 582
 583         return((*dirent->filldir)(dirent->vfs_dirent, name, size, offset,
 584                                   inode, type));
 585 }
 586
 587 static int hppfs_readdir(struct file *file, void *ent, filldir_t filldir)
 588 {
 589         struct hppfs_private *data = file->private_data;
 590         struct file *proc_file = data->proc_file;
 591         int (*readdir)(struct file *, void *, filldir_t);
 592         struct hppfs_dirent dirent = ((struct hppfs_dirent)
 593                                       { .vfs_dirent     = ent,
 594                                         .filldir        = filldir,
 595                                         .dentry         = file->f_dentry } );
 596         int err;
 597
 598         readdir = proc_file->f_dentry->d_inode->i_fop->readdir;
 599
 600         proc_file->f_pos = file->f_pos;
 601         err = (*readdir)(proc_file, &dirent, hppfs_filldir);
 602         file->f_pos = proc_file->f_pos;
 603
 604         return(err);
 605 }
 606
 607 static int hppfs_fsync(struct file *file, struct dentry *dentry, int datasync)
 608 {
 609         return(0);
 610 }
 611
 612 static const struct file_operations hppfs_dir_fops = {
 613         .owner          = NULL,
 614         .readdir        = hppfs_readdir,
 615         .open           = hppfs_dir_open,
 616         .fsync          = hppfs_fsync,
 617 };
 618
 619 static int hppfs_statfs(struct super_block *sb, struct kstatfs *sf)
 620 {
 621         sf->f_blocks = 0;
 622         sf->f_bfree = 0;
 623         sf->f_bavail = 0;
 624         sf->f_files = 0;
 625         sf->f_ffree = 0;
 626         sf->f_type = HPPFS_SUPER_MAGIC;
 627         return(0);
 628 }
 629
 630 static struct inode *hppfs_alloc_inode(struct super_block *sb)
 631 {
 632         struct hppfs_inode_info *hi;
 633
 634         hi = kmalloc(sizeof(*hi), GFP_KERNEL);
 635         if(hi == NULL)
 636                 return(NULL);
 637
 638         *hi = ((struct hppfs_inode_info) { .proc_dentry = NULL });
 639         inode_init_once(&hi->vfs_inode);
 640         return(&hi->vfs_inode);
 641 }
 642
 643 void hppfs_delete_inode(struct inode *ino)
 644 {
 645         clear_inode(ino);
 646 }
 647
 648 static void hppfs_destroy_inode(struct inode *inode)
 649 {
 650         kfree(HPPFS_I(inode));
 651 }
 652
 653 static struct super_operations hppfs_sbops = {
 654         .alloc_inode    = hppfs_alloc_inode,
 655         .destroy_inode  = hppfs_destroy_inode,
 656         .read_inode     = hppfs_read_inode,
 657         .delete_inode   = hppfs_delete_inode,
 658         .statfs         = hppfs_statfs,
 659 };
 660
 661 static int hppfs_readlink(struct dentry *dentry, char *buffer, int buflen)
 662 {
 663         struct file *proc_file;
 664         struct dentry *proc_dentry;
 665         int ret;
 666
 667         proc_dentry = HPPFS_I(dentry->d_inode)->proc_dentry;
 668         proc_file = dentry_open(dget(proc_dentry), NULL, O_RDONLY);
 669         if (IS_ERR(proc_file))
 670                 return PTR_ERR(proc_file);
 671
 672         ret = proc_dentry->d_inode->i_op->readlink(proc_dentry, buffer, buflen);
 673
 674         fput(proc_file);
 675
 676         return ret;
 677 }
 678
 679 static void* hppfs_follow_link(struct dentry *dentry, struct nameidata *nd)
 680 {
 681         struct file *proc_file;
 682         struct dentry *proc_dentry;
 683         void *ret;
 684
 685         proc_dentry = HPPFS_I(dentry->d_inode)->proc_dentry;
 686         proc_file = dentry_open(dget(proc_dentry), NULL, O_RDONLY);
 687         if (IS_ERR(proc_file))
 688                 return proc_file;
 689
 690         ret = proc_dentry->d_inode->i_op->follow_link(proc_dentry, nd);
 691
 692         fput(proc_file);
 693
 694         return ret;
 695 }
 696
 697 static struct inode_operations hppfs_dir_iops = {
 698         .lookup         = hppfs_lookup,
 699 };
 700
 701 static struct inode_operations hppfs_link_iops = {
 702         .readlink       = hppfs_readlink,
 703         .follow_link    = hppfs_follow_link,
 704 };
 705
 706 static int init_inode(struct inode *inode, struct dentry *dentry)
 707 {
 708         if(S_ISDIR(dentry->d_inode->i_mode)){
 709                 inode->i_op = &hppfs_dir_iops;
 710                 inode->i_fop = &hppfs_dir_fops;
 711         }
 712         else if(S_ISLNK(dentry->d_inode->i_mode)){
 713                 inode->i_op = &hppfs_link_iops;
 714                 inode->i_fop = &hppfs_file_fops;
 715         }
 716         else {
 717                 inode->i_op = &hppfs_file_iops;
 718                 inode->i_fop = &hppfs_file_fops;
 719         }
 720
 721         HPPFS_I(inode)->proc_dentry = dentry;
 722
 723         return(0);
 724 }
 725
 726 static int hppfs_fill_super(struct super_block *sb, void *d, int silent)
 727 {
 728         struct inode *root_inode;
 729         struct file_system_type *procfs;
 730         struct super_block *proc_sb;
 731         int err;
 732
 733         err = -ENOENT;
 734         procfs = get_fs_type("proc");
 735         if(procfs == NULL)
 736                 goto out;
 737
 738         if(list_empty(&procfs->fs_supers))
 739                 goto out;
 740
 741         proc_sb = list_entry(procfs->fs_supers.next, struct super_block,
 742                              s_instances);
 743
 744         sb->s_blocksize = 1024;
 745         sb->s_blocksize_bits = 10;
 746         sb->s_magic = HPPFS_SUPER_MAGIC;
 747         sb->s_op = &hppfs_sbops;
 748
 749         root_inode = iget(sb, 0);
 750         if(root_inode == NULL)
 751                 goto out;
 752
 753         err = init_inode(root_inode, proc_sb->s_root);
 754         if(err)
 755                 goto out_put;
 756
 757         err = -ENOMEM;
 758         sb->s_root = d_alloc_root(root_inode);
 759         if(sb->s_root == NULL)
 760                 goto out_put;
 761
 762         hppfs_read_inode(root_inode);
 763
 764         return(0);
 765
 766  out_put:
 767         iput(root_inode);
 768  out:
 769         return(err);
 770 }
 771
 772 static struct super_block *hppfs_read_super(struct file_system_type *type,
 773                                              int flags, const char *dev_name,
 774                                              void *data)
 775 {
 776         return(get_sb_nodev(type, flags, data, hppfs_fill_super));
 777 }
 778
 779 static struct file_system_type hppfs_type = {
 780         .owner          = THIS_MODULE,
 781         .name           = "hppfs",
 782         .get_sb         = hppfs_read_super,
 783         .kill_sb        = kill_anon_super,
 784         .fs_flags       = 0,
 785 };
 786
 787 static int __init init_hppfs(void)
 788 {
 789         return(register_filesystem(&hppfs_type));
 790 }
 791
 792 static void __exit exit_hppfs(void)
 793 {
 794         unregister_filesystem(&hppfs_type);
 795 }
 796
 797 module_init(init_hppfs)
 798 module_exit(exit_hppfs)
 799 MODULE_LICENSE("GPL");
 800
 801 /*
 802  * Overrides for Emacs so that we follow Linus's tabbing style.
 803  * Emacs will notice this stuff at the end of the file and automatically
 804  * adjust the settings for this buffer only.  This must remain at the end
 805  * of the file.
 806  * ---------------------------------------------------------------------------
 807  * Local variables:
 808  * c-file-style: "linux"
 809  * End:
 810  */